Plastic surgery in liver transplantation

Rates of hepatic artery thrombosis in liver transplantation with the use of a microscope: A systematic review

OBJECTIVE

Hepatic artery anastomosis in liver transplantations requires a meticulous technique to minimize the risk of hepatic artery thrombosis (HAT). The microscope helped improve anastomosis techniques in pediatric patients with small caliber vessels. The aim of this review was to compare microsurgical and non-microsurgical techniques on the incidence of HAT in liver transplantations. The secondary objective was to compare HAT incidence between pediatric and adult cohorts and between plastic and transplant surgeons.

METHODS

A systematic review of the literature using Medline, Embase, and Cumulative Index to Nursing and Allied Health Literature (CINAHL) was conducted on studies involving HAT in liver transplantations with microsurgery. Three reviewers performed a full article review and data extraction for studies meeting the eligibility criteria of the study.

RESULTS

Forty-five studies were incorporated in the final analysis. A total of 7346 patients and 7506 liver transplants were included. The mean age was 17 years old with an equivalent distribution between pediatric (51%, n = 3218) and adult patients (49%, n = 3145). A total of 6351 of these transplantations underwent microsurgical repair, against 1157 with non-microsurgical techniques. The overall HAT rate was 4.9%, including 4.2% in the microsurgical group (n = 268) and 8.5% in the non-microsurgical group (n = 98), a statistically significant increase of 4.3%. The occurrence of HAT was 2.6% with a plastic surgeon versus 4.6% with other types of surgeons. When using microsurgical techniques, the HAT rate was 4.2% with living donors versus 7.7% with deceased donors.

CONCLUSIONS

HAT and subsequent liver transplant failure are lower when microsurgical techniques, living donors, and plastic surgeons with a microsurgical training are involved in the operation.

Artery Reconstruction in Right Lobe Living Donor Liver Transplantation: Donor-Recipient Vessel Ratio Is Key to Choosing Recipient Artery

BACKGROUND

The aims of this study were to investigate if recipient artery choice in right lobe living donor liver transplant affects postoperative complications and discuss solutions accordingly.

METHODS

Three hundred fourteen right lobe living donor liver transplantation patients were divided into 2 groups: 163 patients using right hepatic artery as the recipient vessel and 151 patients using left hepatic artery as the recipient vessel. Cases involving 2 recipient blood vessels or the use of other blood vessels as recipient vessels were excluded.

RESULTS

Overall vascular embolism rate in both groups was 1.3%, and our complication rate was lower than those in previous studies. There was no significant difference in complication rate between the groups, but a significant difference in recipient/donor artery size ratio was noted.

CONCLUSIONS

Although left hepatic artery's anatomical position makes it less affected by bile duct anastomosis and thus fewer postoperative complications, we believe that the ratio of the donor-recipient blood vessel size and the length of the anastomosis vessel stumps are the key factors that affect the outcome of the vascular anastomosis.

Reducing the incidence of hepatic artery thrombosis in pediatric liver transplantation: Effect of microvascular techniques and a customized anticoagulation protocol

We aimed to assess the incidence of HAT over three eras following implementation of microvascular techniques and a customized anticoagulation protocol in a predominantly cadaveric split liver transplant program. We retrospectively reviewed pediatric liver transplants performed between April 1986 and 2016 and analyzed the incidence HAT over three eras. In E1, 1986-2008, each patient received a standard dose of 5 U/kg/h of heparin and coagulation profiles normalized passively. In E2, 2008-2012, microvascular techniques were introduced. In E3, 2012-2016, in addition, a customized anticoagulation protocol was introduced which included replacement of antithrombin 3, protein C and S, and early heparinization. A total of 317 liver transplants were completed during the study period, with a median age of 31.7 months. In E1, 22% of grafts were cadaveric in situ split grafts, while the second and third eras used split grafts in 59.0% and 64.9% of cases, respectively. HAT occurred in 9.5% in the first era, 11.5% (P=.661) in the second, and dropped to 1.8% in the third era (P=.043). A routine anticoagulation protocol has significantly reduced the incidence of HAT post-liver transplantation in children in a predominantly cadaveric in situ split liver transplant program.

Use of tissue expansion to facilitate liver and small bowel transplant in young children with contracted abdominal cavities

Liver and small bowel transplant is an established treatment for infants with IFALD. Despite organ reduction techniques, mortality on the waiting list remains high due to shortage of size-matched pediatric donors. Small abdominal cavity volume due to previous intestinal resection poses a significant challenge to achieve abdominal closure post-transplant. Seven children underwent tissue expansion of abdominal skin prior to multiorgan transplant. In total, 17 tissue expanders were placed subcutaneously in seven children. All seven subjects underwent re-exploration to deal with complications: hematoma, extrusion, infection, or port related. Three expanders had to be removed. Four children went on to have successful combined liver and small bowel transplant. Two children died on the waiting list of causes not related to the expander and one child died from sepsis attributed to an infected expander. Tissue expansion can generate skin to facilitate closure of abdomen post-transplant, thus allowing infants with small abdominal volumes to be considered for transplant surgery. Tissue expansion in children with end-stage liver disease and portal hypertension is associated with a very high complication rate and needs to be closely monitored during the expansion process.

Intimal dissection of the hepatic artery following transarterial embolization for hepatocellular carcinoma: an intraoperative problem in adult living donor liver transplantation

The objective of this study was to describe the relationship between intimal dissection (ID) in the recipient hepatic artery (HA) and transarterial embolization (TAE) and highlight the reconstructive methods for the different types of ID encountered in living donor liver transplantation (LDLT). Fifty-four patients with hepatocellular carcinoma underwent LDLT. ID was classified as mild, moderate, or severe, and this classification was based on the extent of intimal injury. Mild, moderate, or severe ID were defined as ID that was less than one-quarter of the circumference of the HA, had reached one-half of the circumference of the HA, or was more than one-half of the circumference of the HA or involved the entire vessel wall, respectively. The reconstructive methods were based on the severity of ID encountered. Forty patients underwent TAE before LDLT, and 23 of these patients (57.5%) had ID. Nine patients had mild ID, 6 had moderate ID, and 8 had severe ID. In the 14 patients who did not undergo TAE, 4 had ID (28.6%; 3 mild and 1 severe). The other 10 patients (71.4%) had normal HA. In mild and moderate ID, the native HA was used after trimming of the HA until a healthy segment was encountered. In severe ID, the HA was reconstructed with alternative vessels. Two HA thromboses occurred postoperatively. TAE increased the risk of developing ID 2-fold. There was no graft loss or mortality in this series due to HA complications. In conclusion, ID of the HA is associated with pretransplant TAE among hepatocellular carcinoma patients undergoing LDLT. Intraoperative recognition of this complication and trimming until good vessel quality is encountered or using alternative vessels are important.

Collaboration with microsurgery prevents arterial complications and provides superior success in partial liver transplantation

Hepatic artery thrombosis is the most common technical complication in liver transplantation. The objective of this study was to investigate the arterial complications of partial liver transplantation using microsurgical technique. At a period of 31-months, we participated in a total of 42 right lobes, 7 left lobes, and 1 whole-liver liver transplantations from cadaveric (n = 20) or living (n = 30) donors. Hepatic artery anastomosis was performed using microsurgical techniques. All anastomoses were accomplished successfully. Fifteen patients expired postoperatively and 35 hepatic artery anastomoses remained patent at a mean follow-up period of 10.6 +/- 8.4 months. The mean diameters of the donor and recipient hepatic arteries were 2.9 +/- 1.2 mm and 3.2 +/- 1.1 mm, respectively. Specific technical challenges were encountered during operation in eight cases (16%). We have found that microsurgical techniques are not only useful for a superior anastomosis but also reliable to adapt to vascular anomalies with less arterial complications. complications.

Could the use of interposition grafts for arterial reconstruction be avoided by more caudate graft placement in living donor liver transplantation?

One of the major challenges in living donor liver transplantation (LDLT) is short and small vessels (particularly the hepatic artery), particularly in segmental liver grafts from living donors. In the present study we report an alternative surgical technique that avoids interpositional vessel grafts or tension on the connection by anastomizing the allograft hepatic vein to the recipient inferior vena cava in a more caudate location. From March 2000 to January 2003, 28 patients (11 women/17 men) underwent 28 LDLT. Until June 2001, the preferred technique for hepatic vein anastomosis was end-to-end anastomosis between the allograft hepatic vein and the recipient hepatic vein (HV-HV) (n = 10). Thereafter an end-to-side anastomosis was performed between allograft hepatic vein and recipient inferior vena cava (HV-IVC) (n = 18). The level of venotomy on the recipient vena cava was decided according to the pre-anastomotic placement of the allograft in the recipient hepatectomy site with sufficient width to have an hepatic artery anastomosis without tension or need for an interposition graft during hepatic artery and portal vein anastomoses. Except the right lobe allograft with anterior and posterior portal branches, all portal and hepatic artery anastomoses were constructed without an interposition graft or tension in the HV-IVC group. Only one hepatic artery thrombosis developed in the HV-IVC group. As a result, this technique may avoid both hepatic artery thrombosis and the use of interposition grafts in living donor liver transplantation.

Hepatic artery reconstruction in living-donor liver transplantation: a review of its techniques and complications

BACKGROUND

Hepatic arterial reconstruction is one of the most difficult procedures in living-donor liver transplantation (LDLT) because the artery used is generally small in diameter and has a short stalk. If hepatic artery thrombosis (HAT) occurs, the recipient clinical course will be unstable. The introduction of microvascular hepatic arterial reconstruction has significantly decreased the incidence of HAT.

METHODS

Fifty-two cases of LDLT were performed from October 1995 to May 2001 in our institution. Hepatic arterial reconstruction was performed under microscopic guidance.

RESULTS

HATs were recognized in 2 cases (3.8%), both of which needed reoperation.

CONCLUSIONS

Surgeons who perform hepatic arterial reconstruction in LDLT should be highly trained in microvascular techniques to decrease the incidence of HAT. This commentary reviews the surgical techniques of hepatic arterial reconstruction and possible complications that may arise in a reconstructed hepatic artery.